<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
<script type="text/javascript" src="js/jquery-1.12.4.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
	var j=json
	$("input").blur(function(){
		$.ajax({
			"url":"CheckUserServlet1",
			"type":"post",
			"dataType":"json",
			"success":function(str){
			}
		});
	});
});		
</script>
</head>
<body>
	用户名:<input type="text" name="userName" id="userName"><span id="err"></span><br/>
</body>
</html>